Many imaging apparatus, such as electrophotographic printers and copiers, ink jet printers and the like, utilize various operating modes and perform different functions that require a "warm-up" time when the imaging apparatus is not in a fully operational state. For example, an imaging apparatus may utilize a ready or operating mode and a standby mode. The operating mode corresponds to the imaging apparatus being in a fully operational status and ready to generate output. The standby mode corresponds to a reduced status in which the imaging apparatus remains powered up, but one or more of its imaging components is not ready to operate. For example, the temperatures of the apparatus' thermal components, such as a fuser or a heated ink jet print head, may be lowered. In an electrophotographic printer or copier, the laser mirrors may require "spinning up" before the imaging process may proceed. These situations are also encountered when the imaging apparatus is turned on from the off status.
Placing an imaging apparatus in a standby mode has the advantages of reducing power consumption and reducing thermal wear on the thermally sensitive components of the apparatus. For example, in a solid ink jet color printer, the temperature of the print head during printing and in the operating mode between print jobs may be in the range of about 140.degree. C. In a standby mode, the temperature of the print head maybe lowered to a range of between about 95.degree. C. and about 105.degree. C., thereby reducing thermal wear and power consumption.
When an imaging apparatus is in a standby made, the imaging apparatus must return to the operating mode before imaging can begin. This imposes an undesirable delay on the imaging process. For example, in the Phaser.RTM. 360 solid ink color printer manufactured by Tektronix, Inc., the assignee of the present application, the printer can require approximately five minutes to raise the temperatures of the print head and associated ink reservoirs from the standby mode to the operating mode.
It is desirable to avoid warm up delays whenever possible. It is also desirable to maximize the time in a standby mode between imaging commands to minimize thermal wear and power consumption. One attempt to address these needs has involved the use of a timer to track the elapsed time between print commands. For example, the Phaser.RTM. 360 printer remains in the operating mode for a fixed period of time (four hours) after a print command is received, and thereafter enters the standby mode. When the next print command is received, the printer must warm-up from the standby mode before printing can begin.
Using a timer to control whether the printer is in an operating or a standby mode inevitably creates situations in which a print command is received while the imaging apparatus is in the standby mode. A timer also maintains the imaging apparatus in the operating mode for a fixed period of time regardless of whether imaging commands are typically received during this period. In this regard, the timer may keep the imaging apparatus in the operating mode even though print commands are rarely received during this period.
What is needed is an intelligent usage tracking system that is capable of monitoring actual use over a period of time and controlling the imaging apparatus based on prior use to minimize warm-up delays and maximize time in a standby mode.